1. Field of the Invention
This invention relates to processing trim meat pieces. In one of its aspects, the invention relates to upgrading trim pieces of meat to a fraction having a higher lean meat content and a fraction having a higher fat content.
2. State of Prior Art
Knudsen, U.S. Pat. No. 3,396,280, discloses a method for determining the fat content of trimmings or similar pieces of meat by photoelectrically sensing the color of each such meat piece and integrating the value thus photoelectrically sensed to give a percentage of fat content in a batch of meat. The batch can then be upgraded by adding lean pieces of meat if the lean meat content is too low.
Badgley, U.S. Pat. No. 3,499,527, discloses a method and apparatus for selectively separating meat products such as strips of bacon by projecting a green light on the surface areas of the meat products and detecting the intensity of the green light reflected therefrom. Typically, a batch of meat products, such as bacon strips, will be photoelectrically measured at a particular time to make certain that the meat products have a predetermined ratio of lean to fat meat. In the event that the products have a content of meat which is too low, a warning light is turned on and the meat products are removed selectively from a conveyor system.
Kail, in U.S. Pat. No. 3,154,625, discloses a photometric method for grading beef wherein a portion of a ribeye meat cut of beef is photoelectrically viewed with and without a filter, and the light value detected is correlated with the weight of the animal to give a meat yield and a quality grade for the animal.
Walter, in U.S. Pat. No. 2,373,361 discloses an apparatus for separating lean meat from fat tissue wherein fat trimmings are ground up and deposited on a belt. The ground meat is pressed into a thin layer on the belt and then cut into thin ribbons of about 1/2 inch to 1 inch in thickness. Light reflected from the ribbons is sensed by a photoelectric cell. Scrapers are operated in accordance with the light detected from the photoelectric cell to scrape lean meat from the belt into a first chute. The fatter portions remain on the belt and are later scraped therefrom into a second chute. The process depends on the grinding of the meat into coarse particles so that it can be flattened onto a belt and also depends on the stickiness of the meat to adhere to the belt.